Conventionally, in the electrical apparatuses for use in the home, various technologies are used to reduce electricity consumption. For example, a function of automatically shutting down the power when an electric apparatus is not in use, and a function such as a low power mode of reducing the electricity consumption than during normal operation are known.
In recent years, there has been proposed a technology for connecting the electrical apparatus in the home to a network and controlling each apparatus through communication over the network.
As a technology for realizing such network for the home, a Power Line Communication (PLC) has been noteworthy. The PLC means a system for attaining the bidirectional communication using the power line as a transmission path by superimposing a high frequency signal on the existent power line of 100 V (50/60 Hz) (e.g., refer to Japanese Patent Application Laid-Open No. 2004-7497).
In the PLC, the existent power incoming line, a socket (electrical outlet) or a plug can be directly used, whereby new wiring works are unnecessary. Also, the PLC can be connected simply by inserting the plug into the socket, whereby plug and play is permitted without needing the complex settings.
In the case where an electrical apparatus in the home is connected to each other via the network such as the PLC, to be controlled, it is required that a circuit for receiving a control signal from the network is operable at any time in each apparatus.
Therefore, the standby power consumed while the power is off is increased, resulting in a problem that the total electricity consumption is increased.